1. Retraining of the 1232 Main Dipole Magnets in the LHC
- Author
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Daniel Wollmann, M. Bednarek, Ezio Todesco, Per Espen Hagen, Sandor Feher, Andrzej Siemko, S. Le Naour, Bernhard Auchmann, Arjan Verweij, J. Ph. Tock, Gerard Willering, Iván Romera, Michele Modena, Z. Charifoulline, L. Bottura, and Jens Steckert
- Subjects
010302 applied physics ,Physics ,Large Hadron Collider ,Particle accelerator ,Superconducting magnet ,Condensed Matter Physics ,01 natural sciences ,Accelerators and Storage Rings ,Synchrotron ,Electronic, Optical and Magnetic Materials ,law.invention ,Nuclear physics ,Magnetic circuit ,Dipole ,law ,Dipole magnet ,Magnet ,0103 physical sciences ,Physics::Accelerator Physics ,Electrical and Electronic Engineering ,010306 general physics - Abstract
The Large Hadron Collider (LHC) contains eight main dipole circuits, each of them with 154 dipole magnets powered in series. These 15-m-long magnets are wound from Nb-Ti superconducting Rutherford cables, and have active quench detection triggering heaters to quickly force the transition of the coil to the normal conducting state in case of a quench, and hence reduce the hot spot temperature. During the reception tests in 2002-2007, all these magnets have been trained up to at least 12 kA, corresponding to a beam energy of 7.1 TeV. After installation in the accelerator, the circuits have been operated at reduced currents of up to 6.8 kA, from 2010 to 2013, corresponding to a beam energy of 4 TeV. After the first long shutdown of 2013-2014, the LHC runs at 6.5 TeV, requiring a dipole magnet current of 11.0 kA. A significant number of training quenches were needed to bring the 1232 magnets up to this current. In this paper, the circuit behavior in case of a quench is presented, as well as the quench training as compared to the initial training during the reception tests of the individual magnets.
- Published
- 2016